Claude Fable 5.1 vs union-alpha
Wins 4 of 4 areas
Coding · Reasoning · Math · Following instructions
Wins 0 of 4 areas
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Claude Fable 5.1 is the stronger all-rounder.
Scores updated · 7 tests both models report · How we compare
Where each one wins
Tests won in each of the four areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
Reasoning, math and following instructions rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Claude Fable 5.1 pulls ahead
- Follows detailed instructions exactlyLiveBench · Instruction Following+13.5points ahead
- Fixes real GitHub issues, working as an agentLiveBench · Agentic Coding+11.4points ahead
- Fresh logic puzzles that change regularlyLiveBench · Reasoning+10.9points ahead
Where union-alpha pulls ahead
No clear win on a test scored out of 100.
Every test, side by side
All 7 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Fable 5.1
- LiveBench · Agentic CodingClaude Fable 5.1 by 11.466.154.7+11.4
- LiveBench · CodingClaude Fable 5.1 by 4.286.482.2+4.2
ReasoningClaude Fable 5.1
- LiveBench · ReasoningClaude Fable 5.1 by 10.991.780.8+10.9
Following instructionsClaude Fable 5.1
- LiveBench · Instruction FollowingClaude Fable 5.1 by 13.57359.5+13.5
Other results2 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- livebench_data_analysisClaude Fable 5.1 by 5.780.374.6+5.7
- livebench_languageClaude Fable 5.1 by 3.689.585.9+3.6
Questions people ask
Which is better, Claude Fable 5.1 or union-alpha?
Claude Fable 5.1 wins all four areas where both have results: coding, reasoning, math and following instructions. union-alpha wins none.
Which is better for coding?
Claude Fable 5.1. It wins 2 of the 2 coding tests both models report; union-alpha wins none.
How do you compare the two?
We use the 7 benchmark tests both models have published scores on. The verdict counts the 5 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 2 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.